Final answer:
The work done by a 9.0 V potential difference in moving 8.50× 10¹⁸ electrons is 12.24 Joules. Hence, option (a) is correct.
Step-by-step explanation:
The question asks about the work done by a potential difference in moving a certain number of electrons.
To find the work done, we can use the formula:
Work (W) = Charge (Q) × Potential Difference (V).
Since 1 electron has a charge of about -1.60 × 10⁻¹⁹ C, the total charge of 8.50× 10¹⁸ electrons is -8.50 × 10¹⁸ × 1.60 × 10⁻¹⁹ C = -1.36 Coulombs.
The potential difference is 9.0 V, so the work done would be W = -1.36 C × 9.0 V = -12.24 Joules.
Since work is a scalar quantity, we take the absolute value, which means the work done is 12.24 Joules.
This is closest to option a. 12.2 J.